


Sins of the Father

by Nanenna



Category: Undertale (Video Game)
Genre: Aftertale Sans | Geno (Undertale), Alternate Universe - Aftertale (Undertale), Alternate Universe - Angels & Demons, Alternate Universe - Monsters Weren't Sealed Underground, Alternate Universe - Reapertale (Undertale), Angels vs. Demons, DestructiveDeath (Undertale Ship), Fallen Angels, Fanchild Goth (Undertale), Inaccurate Christianity, M/M, Memory Loss, Minor Violence, Non-Graphic Violence, Outcode Error (Undertale), Outcode Error/Reapertale Sans (Undertale), Patchwork AU, Reaperror (Undertale Ship), Reapertale Sans (Undertale), Religious Imagery & Symbolism
Language: English
Status: In-Progress
Published: 2020-09-02
Updated: 2020-09-02
Packaged: 2021-03-06 23:42:04
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,166
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26257348
Author URL: https://archiveofourown.org/users/Nanenna/pseuds/Nanenna
Summary: Reaper is the angel of Death, a cog in the great cosmic machine that keeps the world spinning, a linchpin piece in the cycle of Life and Death. Sans is the angel of Judgement, or he was until he was kicked out of Heaven and became a Fallen angel, destined to eventually succumb to his Fall and become a full fledged demon. Reaper never knew why. Perhaps he should have asked harder, or at all.
Relationships: Sans/Sans (Undertale)
Comments: 12
Kudos: 48





	Sins of the Father

**Author's Note:**

  * Inspired by [Reapertale](https://archiveofourown.org/external_works/763548) by Renrink. 
  * Inspired by [Aftertale](https://archiveofourown.org/external_works/763551) by Crayon Queen. 



> There isn't just some or even a lot of Christian religious imagery in this fic, it's literally made of it. I'm using the Christian mythology the same way I have used Greco/Roman mythology, faerie lore, and East Asian mythology in the past: it's just another slew of interesting tropes and imagery that I can use to tell a story like I couldn't using a different mythology. If you have issues with that please turn back now and save us both a lot of trouble. Thank you.
> 
> The beautiful cover illustration was provided by the ever wonderful [Perville on Twitter](https://twitter.com/artville1985), thank you so much for this gorgeous piece of art! Go check them out! Or just click [here](https://twitter.com/artville1985/status/1301278880058290186) to go straight to the full sized piece.

* * *

Reaper sighed as he descended from Heaven to Earth, he wasn’t looking forward to this. Oh his job usually had him working down on Earth just like most angels, but he spent the vast majority of his time down in the guts working to keep the gears turning, not up on the surface interacting with mortals. But still, an Order from God had to be obeyed. The mortals were failing to follow His teachings and a Judgment had been called for. Unfortunately that lot fell to Reaper these days. He spent some time wandering back and forth over the Earth as he tried to figure out how best to start this Judgment, then inspiration struck! Something to hearken back to the old days and rules mortals seemed to have thrown aside. Something small and easily overlooked, riding on the back of vermin. Reaper had just sent his Judgment on its way when he felt something snag his arm. Confused, Reaper pulled his arm up to look at whatever had gotten caught.

Something long and thin, he would have thought it was a spider web if not for its bright red coloring. His scythe was already in his hand as more thin strings were already looping over his head and wings. With a quick motion he sliced them, “Show yourself, demon!” Reaper’s grip on his scythe tightened as he seethed, only a demon could or would be so brazen as to attempt trapping an angel like this.

“Heh, guess again.” A pale figure came walking out of the nearby trees, strange movement around his head and bright red dripping from his face, chest, and fingers where it ran down the strings clutched tightly in his grip. Anyone else might mistake it for blood, but Reaper had seen enough of that in his line of work to know it was the wrong shade of red for that. A few ragged feathers the same shade of red as the dripping strings fluttered to the ground in their wake, a clear sign that they had wings even if they were tucked out of sight. Not a demon then, but something far more pitiable: a fallen angel that hadn’t yet finished his transition to a demon. One Reaper recognized.

“Sans?”

The figure frowned and threw more strings over Reaper’s head, “Don’t call me that!”

“What? But… Sans,” Reaper started.

“That’s not my name anymore! Sans is dead, has been for a long, long time. Call me Genocide if you have to call me anything.” He started walking forward again, Reaper could now make out that the strange movement around his head was in fact a mass of glitches, a sign of just how powerful he still was even after having Fallen.

“Geno…? I don’t understand.”

 ~~Sans~~ Geno scoffed, “Of course not, you still get to live up there with all the other goody goodies, trapped in your own little perfect bubble. Genocide is more honest, it was my job after all.”

Reaper shook his head, “No, no it wasn’t!” Reaper protested vehemently, for all the good he knew it would do. Fallen angels were notoriously unstable. “You were the Judge, remember?”

“Judgment, genocide, it was all the same thing.” Geno gave a nonchalant shrug before slowly walking closer, “I wasn’t the one who passed Judgment, that was already done before I even started. No, my job was just to carry out His Judgments: go kill everyone in this city or that, kill all the firstborn sons, wipe out this army, that nation, man woman child and all. Judgment, hah! They were all genocides in one form or another, He just sent me instead of getting His own hands dirty. And look how easily I’m replaced, now He has you doing the job instead.” Geno was now practically touching Reaper, his one working eye socket squinting up at Reaper. “Oh, it’s you. Hmph, if He’s got _you_ doing my job then He’s skipping all pretenses now.”

“Sa-… Geno. It’s been over a millennium, how are you…” Reaper trailed off.

“Still sane?”

“Not a demon yet?”

Geno glared at Reaper, his fists tightening in anger. “Like you even care. Over a millennium, you just said it yourself, and you never tried to find me, never came looking.”

Reaper felt his guilt settle on his shoulders, “Geno, it was already too late. You were already Fallen, there’s no going back from that.”

“Clearly. You don’t even care, you weren’t even looking for me now! Just down here mucking about the humans on His orders without a single thought about me.”

“Of course I care!”

“Yeah, you care about Sans, you don’t even know Geno. And Sans died that day, thrown out like garbage while you did nothing.”

“I didn’t even know it was happening, I didn’t find out until after you were gone. I still don’t even know why.”

Geno huffed, “Of course not. Did you even ask? Nah, don’t bother answering, it doesn’t matter. Like you said, it was too late for Sans, it’s way too late for Geno. Can’t change the past no matter how much it still hurts.”

“I’m here now.”

Geno stomped a foot, “That doesn’t do me any good now! I needed you, we needed you! But you decided it was better to stay up there and leave us to fend for ourselves rather than risk pissing off God. We all have to live with the choices _you_ made.”

“Geno… I missed you.” He felt a few tears slip from his sockets. “I thought about you every day, I really did.”

“Yeah? Me too.” Geno started to reach up, his hand coming within a hair’s breadth of touching Reaper’s face. Then the hand tightened into a fist and fell to his side, “No, no I won’t.” He yanked, the strings around Reaper tightened and flung him back. “Go away, I don’t want to ever see you again.”

“Sans! Wait!”

Another yank of the strings sent Reaper tumbling head over heels. By the time he scrambled to sit up, tearing the slack, goopy strings off himself, Geno had already vanished.

* * *

It had been several centuries since Reaper had last seen Sans and first met Geno, and so far it was also the last. He had no idea why he continued searching, so far as he knew there was nothing to be done to help a Fallen. Eventually Geno would succumb to his Fall and finally become a demon. But if he managed to live for over a millennium without succumbing surely he could go another. Sans had been legendarily stubborn, Reaper had no doubt simply changing his name to Geno hadn’t changed that. And above all Reaper still had faith. So when he felt something like a spider web snag his robe again he turned around eagerly only to find a black boned skeleton demon grinning manically at him. The demon was all wrong, with red eyes and yellow teeth. The string was all wrong too, a deep shade of blue and made not of corrupt mana but of code that stung where it touched his bare bones.

“Well what have we here?” the demon asked like it didn’t know. It reached up with fingers Reaper just then noticed were the same shades of red and yellow, it grabbed the blue tears leaking from its eyes. Only instead of tears they turned out to be more strings it tried to loop over Reaper.

Reaper used his scythe to sever the strings, “A demon that foolishly thinks it can stand up to an angel!”

The demon pulled out more strings and tossed them towards Reaper, intent on recapturing him. “I’m pretty sure we have an angel that foolishly thinks it can stand up to The Destroyer.”

Reaper scoffed as he easily dodged the latest round of strings, “Everyone knows angels are stronger than demons.”

The demon frowned, “That’s stupid. You’re stupid! A stupid abomination!”

Reaper laughed, “You’re calling me an abomination?!” The audacity of this demon! Or perhaps it was simply delusional, Reaper almost pitied the poor creature. That was until his latest dodge had him flying through several strings he hadn’t noticed loosely strung between some trees. Unfortunately his instinct to flail to get them off only tangled him further. The demon tossed more strings over him, then pulled them all tight. It was then Reaper noticed what looked to be spider legs sprouting from the demon’s back, mostly just as black as the rest of his bones with the same red and yellow tips as the demon’s fingers. Reaper tightened his grip on his scythe as he tried to get it at an angle he could cut the strings.

“Now who’s the stupid abomination, stupid?”

“You’re the one who’s an affront to God!” Reaper huffed distractedly. Maybe if he kept the demon talking he’d have time to get out of this spider’s web.

The demon scoffed, “It’s _His_ fault demons exist at all, so I’m just doing His will when I do my job and destroy everything He’s ever made. Clean up all his dirty creations.” The demon was stepping closer, its strings pulling tighter. “I haven’t gotten an angel yet, I wonder what’ll happen whe-”

A pair of sickles spun through the air and severed the strings where they were pulled tight between the two of them. The demon only scoffed and turned to look towards the new intruder while Reaper was frozen in shock. Those sickles had been holy weapons, and more shockingly they held his power.

“Gothy, why’d you interrupt us? I was about to test a theory,” the demon whined.

“Dad, what are you doing? We shouldn’t mess with angels, remember?”

Reaper looked over to see an angel walking towards them. A regular looking skeleton, aside from only having one pip, wearing mostly white and a little black with an all too familiar tattered red scarf around their throat.

“Let’s just go,” the strange angel said while picking up their sickles.

“Who are you?” Reaper blurted out.

The stranger sighed, the pointed at the demon. “My name is Goth, and I’m his son. And we’re leaving now, bye.”

The demon just scoffed.

“That doesn’t make any sense,” Reaper insisted, “you’re an angel and that’s a demon.”

“Rude!” The demon hollered before grousing quietly to himself, “I have a name, you know.”

“All demons used to be angels,” Goth said as he walked past. “C’mon, Dad, let’s go.”

The demon rolled his mismatched eyes, but obligingly started walking.

“Wait!” Reaper quickly tore off the bits of string still wrapped around him and started floating after them, “How do you have the same power as me? Only my brother Respite has the same power. And I’ve never seen you in Heaven, but you’re not Fallen? What’s going on? Who are you really?”

“Those are some good questions,” the demon said while squinting back at Reaper, then to Goth at his side. “Gothy?”

Goth sighed again, “I already told you: I’m his son.”

“A demon spawned an angel? Yeah right.” If he had pips Reaper would be rolling them.

“I have a name, you numbskull!”

“I already told you, all demons used to be angels.”

“Angels can’t have children,” Reaper insisted. “I’m not even sure if demons can either.”

Goth and the demon both scoffed, but it was Goth that spoke, “Haven’t you ever heard of the nephilim? I thought they happened after you were born, Death.”

“Oh, right, those.” That had been a long time ago, and God had forbidden it from ever happening again. “But you don’t look human.”

“I’m not.”

“Then why’d you bring them up?”

“Because the nephilim are proof angels can have kids???”

The demon was snickering at this point.

“So then who’s your mother?” Reaper asked, now far too invested to stop.

Goth stopped and sighed yet again, the heaviest one so far. “Reaper, angel of Death, meet my mother: Error, demon of Destruction. Now will you go away and leave us alone?”

“I think I would remember giving birth,” Error said indignantly.

“You can’t remember what you had for breakfast,” Goth shot back.

Error shrugged, “Fair enough.”

“So then who’s the father?” It couldn’t be Respite, could it? That might explain the powers, kinda. Respite was the brother with the closest powers, but his were more focused on dealing with the Souls of the dead, not death itself.

Goth paused and briefly closed his eyes. “Who knows? I never met him.”

Error looked back and forth between Goth and Reaper, a strange glint in his mismatched eyes. Then he huffed, “Well this has been fun and all, but I’m bored now. C’mon Gothy, let’s go.” He flicked a hand and several strings looped around Reaper before he could react and he found himself slammed into the nearest tree trunk. The strings pulled tight, leaving him tied to the tree.

“Hey! Let me go!”

“Ha!” Error crowed, “You really are stupid! Bye bye, abomination!” Error waved cheerfully while Goth just kept walking.

**Author's Note:**

> Okay, that's the start. I have no idea how often I'll be updating or even where it's going, but I had to get this out there and started. Tada!


End file.
